patch 9.0.1767: '.-' no allowed in highlight group names
Problem: '.-' no allowed in highlight group names
Solution: Allow dot and hyphen characters in highlight group names
Allow dots and hyphens in group names. There does not seem
to be any reason for these to be disallowed.
closes: #12807
Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Gregory Anders <greg@gpanders.com>
Co-authored-by: Sean Dewar <seandewar@users.noreply.github.com>
diff --git a/runtime/doc/syntax.txt b/runtime/doc/syntax.txt
index 8a5e5f4..17f8139 100644
--- a/runtime/doc/syntax.txt
+++ b/runtime/doc/syntax.txt
@@ -214,10 +214,10 @@
thing. These are then linked to a highlight group that specifies the color.
A syntax group name doesn't specify any color or attributes itself.
-The name for a highlight or syntax group must consist of ASCII letters, digits
-and the underscore. As a regexp: "[a-zA-Z0-9_]*". However, Vim does not give
-an error when using other characters. The maximum length of a group name is
-about 200 bytes. *E1249*
+The name for a highlight or syntax group must consist of ASCII letters,
+digits, underscores, dots, or hyphens. As a regexp: "[a-zA-Z0-9_.-]*".
+However, Vim does not give an error when using other characters. The maximum
+length of a group name is about 200 bytes. *E1249*
To be able to allow each user to pick their favorite set of colors, there must
be preferred names for highlight groups that are common for many languages.